Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 38,904	$ 23,996	$ 74,149	$ 48,488
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(308)	113	(236)	(71)
Net change in unrealized gains (losses) on available-for sale securities	255	96	206	262
Other comprehensive income (loss)	(53)	209	(30)	191
Comprehensive income	$ 38,851	$ 24,205	$ 74,119	$ 48,679

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=51831270

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